Answer:
Step-by-step explanation:
To determine the time when the height is 40 meters above the ground, we would substitute 40 for h in the given equation. It becomes
1.2 + 4t0t - 5t² = 40
5t² - 40t + 40 - 1.2 = 0
5t² - 40t + 38.8 = 0
The general formula for solving quadratic equations is expressed as
x = [- b ± √(b² - 4ac)]/2a
From the equation given,
a = 5
b = - 40
c = 38.8
Therefore,
t = [- - 40 ± √(- 40² - 4 × 5 × 38.8)]/2 × 5
t = [40 ± √(1600 - 776)]/10
t = [40 ± √824]/10
t = (40 + 28.71)/10 or x = (40 - 28.71)/10
t = 6.871 seconds or t = 1.129 seconds
Answer:

it helps you.
Step-by-step explanation:
✍️✍️✍️by:- jay
Answer:
5>t
Step-by-step explanation:
45 > 12t + 3(t -8) - 6 multiply 3 times t-8
1) 45 > 12t + 3t - 2 - 6 combine alike terms
2) 45 > 15t - 30 isolate the variable by adding 30
3) 75 > 15t divide by 15
4) 5 > t
Answer:
Step-by-step explanation:
i think that it is C but not 100% sorry
The pack of pencils weighs 21.6 grams because 0.9 times 24 is 21.6